M S Mellema | PubMed Health

PubMed2001

Comparison of results of thoracic radiography, cytologic evaluation of bronchoalveolar lavage fluid, and histologic evaluation of lung specimens in dogs with respiratory tract disease: 16 cases (1996-2000).

OBJECTIVE: To compare results of thoracic radiography, cytologic evaluation of bronchoalveolar lavage (BAL) fluid, and histologic evaluation of biopsy and necropsy specimens in dogs with respiratory tract disease and to determine whether histologic evaluation provides important diagnostic information not attainable by the other methods. DESIGN: Retrospective study. ANIMALS: 16 dogs. PROCEDURE: BAL fluid was classified as normal, neutrophilic, eosinophilic, mononuclear, mixed, neoplastic, or nondiagnostic. Radiographic abnormalities were classified as interstitial, bronchial, bronchointerstitial, or alveolar. Histologic lesions were classified as inflammatory, fibrotic, or neoplastic, and the predominant site of histologic lesions was classified as the alveoli, interstitium, or airway. RESULTS: The predominant radiographic location of lesions correlated with the histologic location in 8 dogs. Of 11 dogs with histologic evidence of inflammatory disease, 8 had inflammatory BAL fluid. Of the 2 dogs with histologic evidence of neoplasia, 1 had BAL fluid suggestive of neoplasia, and the other had BAL fluid consistent with septic purulent inflammation. Two dogs without any histologic abnormalities had mononuclear or nondiagnostic BAL fluid. Two dogs with histologic evidence of fibrosis had mononuclear or mixed inflammatory BAL fluid. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that although thoracic radiography, cytologic evaluation of BAL fluid, and histologic evaluation of lung specimens are complementary, each method has limitations in regard to how well results reflect the underlying disease process in dogs with respiratory tract disease. Lung biopsy should be considered in cases where results of radiography and cytology are nondiagnostic.

Animals↗

PubMed2000

Weaning from mechanical ventilation.

Patients that require positive pressure ventilation to maintain sufficient alveolar ventilation or pulmonary gas exchange may eventually reach a point in the course of their care wherein mechanical ventilation is no longer necessary. This process of transferring the work of breathing from the ventilator back to the patient is referred to as ventilator weaning. The term "ventilator weaning" may be used to refer to all methods by which this transfer of workload may be accomplished. In many patients, particularly those with short-lasting or readily correctable causes of respiratory insufficiency (e.g., general anesthesia), the discontinuation of positive pressure ventilation may be easily achieved. Indeed, in patients awakening from general anesthesia, the axiom "awake enough to blink, awake enough to breath" may prove to be a sufficient guideline. However, in those patients requiring long-term mechanical ventilatory support, the process can prove to be both frustrating and exceptionally challenging. It is of crucial importance to identify those patients that may be successfully weaned because of both the financial impact of prolonged intensive care unit hospitalization and the risks imposed on the patient by the process of positive pressure ventilation. To be able to predict which patients may be ready to be weaned from the ventilator requires an understanding of the balance between the work of breathing (ventilatory load) and the ability of the patient's respiratory pump to meet those needs (ventilatory capacity). The management of patients experiencing difficulty during the weaning process requires that the clinician recognize imbalances between ventilatory load and capacity and to correct these imbalances once identified.

Algorithms↗